1. Field of the Invention
The present invention relates to a connecting unit, a band and an electronic device including the band.
2. Description of Related Art
Generally, as a band such as a wristwatch band formed by connecting a plurality of segment members and as a connecting unit of the segment members, in cited document 1 (Japanese Utility Model Application Laid Open Publication No. S60-182811), there is described a type which is configured so that a pair of first pipes are provided at an end of the segment member, a second pipe disposed between the pair of first pipes is provided at an end of another segment member which is connected to the segment member, and a pin member is inserted to each pipe of the first and the second pipes in the state where the second pipe and the pair of first pipes are disposed in series to sequentially connect a plurality of segment members.
Such a band and a connecting unit thereof of a wristwatch and the like are configured so that a stepped hole including a small diameter hole section and a large diameter hole section inside the second pipe is formed, a fastening ring is fit into the large diameter hole section of the stepped hole and a pin member inserted into each of the first and second pipes is fastened by the fastening ring so as to prevent the pin member from getting out of the side of the band, for example.
However, in a band which is formed by connecting a plurality of segment members, strong force is applied to a portion connecting the segment members in a case where the segment members move when the band is used, for example.
Therefore, as described in Patent Document 1, when a fastening ring for preventing falling off of the pin member is disposed inside the second pipe, the fastening ring is easily affected by the move between the segment members and is easily deformed due to applied pressure and ablation with use.
Further, there is also a possibility that strength cannot be maintained due to corrosion of the fastening ring and such like by sweat and such like coming in from between the first pipes and the second pipe.
In such case where a fastening ring is deformed or strength of the fastening ring is lowered, there is a problem that a pin member which is fastened to be fixed by the fastening ring is easy to fall off.
On the other hand, if the pin member is completely fixed so as not to fall off from the band, there is a problem that the segment member cannot be attached and removed without using a special tool or the like and a general user who purchased a wristwatch or the like including the band cannot adjust the length of the band easily.
Though a shop assistant or the like performs adjustment when the wristwatch or the like is purchased at a shop, it is inconvenient if the general user cannot attach and remove a segment member to adjust the size of the band by himself or herself when size adjustment is needed after purchase of the wristwatch or when the wristwatch is purchased by mail order, for example.